Curated OER
Concurrent Lines in Triangles
Students explore the concept of concurrent lines in triangles. In this concurrent lines in triangles lesson, students work in groups to investigate properties of concurrent lines in acute, right, and obtuse triangles. Students use a...
Curated OER
Exploring Geometric Mean
Students solve problems using geometric means. In this geometry lesson, students create altitudes in right triangles. They use Cabri software to move the triangle around and observe different sides and angles.
Curated OER
Exploring Geometric Mean
Student identify the solution using geometric mean. In this geometry lesson, students create right triangles where the altitude of the triangle is the side containing the right angle. They modify shapes using Cabri software and observe...
Curated OER
Constructions of Isosceles and Equilateral Triangles
Students explore the difference between drawing and constructing a triangle utilizing The Geometer's Sketchpad on the computer. They create, develop and script constructions for both isosceles and equilateral triangles. Each student has...
Curated OER
Finding the Area of Triangles
Twelfth graders apply the formula for finding the area of a triangle to various problems. They work real life problems for finding the area of a bathroom and the cost of tiling it. They play a game, Triangle Bingo, where they match...
Curated OER
Contructions and Conjectures
Students make constructions and conjectures. In this geometry lesson, students construct right, acute and obtuse angles using a straight edge and a protractor. They investigate parallel lines and the angles formed by the angles.
Curated OER
Determining the Uniqueness of a Circle
Students use this lesson to determine how circles are different from other shapes. In groups, they determine the accuracy of three theorems based on the uniqueness of circles. They use a software program to hypothesize about the...
Curated OER
Circles
Students review the definition of a circle and the general formula for a circle to specific problems. They also write the equation for a circle given the center and radius of the circle. Students then define a circle using either the...
Curated OER
Triangle Fundamentals Homework
In this geometry worksheet, students identify the missing angles of non right triangles using the angle sum theorem. They solve for the unknown using algebra. There are 21 questions.
Curated OER
Exploring Centers of a Triangle: Part 1
Pupils use problem solving skills, formal geometry, and The Geometer?s Sketchpad. They model and solve two real-world problems by constructing the in center and circumcenter of triangles.
Cuemath
Cuemath: Perpendicular Bisectors
Provides a definition and examples of perpendicular bisectors.
CK-12 Foundation
Ck 12: Geometry: Midpoints and Segment Bisectors
[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to calculate midpoints and use the definitions of segment bisectors and perpendicular bisectors.
Texas Instruments
Texas Instruments: Finding the Shortest Path
Students discover the shortest distance light travels from an object to the human eye, as the light from the object reflects off a single mirror. In the process they learn about reflection in a line, congruent angles, angle bisectors,...
Wolfram Research
Wolfram Math World: Perpendicular Lines
This site explains what perpendicular means geometricly in mathematics, gives reference to orthoginality, and explains notation for perpendicular segments or lines.
Illustrative Mathematics
Illustrative Mathematics: G Srt Shortest Line Segment From a Point P to a Line L
For this task, students develop an understanding that the shortest path from a point to a line always meets the line at a right angle. Aligns with G-SRT.C.8.
ClassFlow
Class Flow: Triangle Segments
[Free Registration/Login Required] In this flipchart, students use the interactive features of Activstudio to understand how to use the properties of perpendicular bisectors, angle bisectors, medians and altitudes of a triangle.
Math Open Reference
Math Open Reference: Line Segment Bisector
Learn about line segment bisectors with this helpful reference tool. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Oswego City School District
Regents Exam Prep Center: Geometry Vocabulary Resources
A list of geometry definitions and a matching activity.
BBC
Bbc: Ks3 Bitesize: Constructions and Locus
This BBC Bitesize focuses on constructions and locus. To understand this activity, you must already know how to define perpendicular, bisect, and locus.
Texas Instruments
Texas Instruments: Triangle Properties Assessment
This activity uses Cabri Jr. to assess the students' knowledge of various segments related to triangles: perpendicular bisector, median, angle bisector, midsegment, and altitude.